GAP

Effectiveness and safety of gabapentin versus placebo as an adjunct to multimodal pain regimens in surgical patients: A placebo controlled, double blind randomised controlled trial

Summary

Gabapentin is a medicine used to treat epilepsy and pain caused by damaged nerves. Recently, doctors have begun using gabapentin to treat pain after an operation, with the intention of reducing the amount of other drugs needed while maintaining good pain relief. Doctors want to try to reduce the amount of other drugs because they cause side effects, often delaying discharge from hospital and leading to slower recovery. There is uncertainty about whether adding gabapentin to the usual drug regimen will result in good pain relief, fewer side effects overall (counting side effects from all of the drugs used to treat pain) and faster recovery after surgery.

We want to conduct a study known as a randomised controlled trial (RCT), in which patients undergoing different types of surgery (heart, chest/lungs and belly/gut) are allocated by chance to receive gabapentin or an identical looking dummy pill in addition to the usual drug regimen for each type of surgery. We will give patients gabapentin or a dummy pi ll one hour before surgery and for two days after surgery. Every other aspect of care will stay the same. We will then compare information about participants who received gabapentin with information about participants who received the dummy pills to determine whether gabapentin reduces the amount of time patients stay in hospital after the operation, the amount of other pain medication they take, and to assess how gabapentin influences pain in hospital and three months after surgery. We will also perform a health economic analysis to determine whether using gabapentin provides better health outcomes for patients undergoing surgery and is cost-effective for the NHS relative to current pain management protocols.

We have chosen to conduct the study in patients undergoing different types of major surgery (heart, chest/lungs and belly/gut), rather than just one. We are using this approach because we want to ensure that the results can be applied to patients undergoing different operations and who receive different types of care. We will conduct the study in two phases. In phase 1, we will determine whether we can recruit patients from the three different types of surgery and whether patients are able to take gabapentin or dummy pill as instructed. We expect Phase 1 to take a year. If successful, we will move on to Phase 2 and continue recruiting. We hope to recruit a total of 1500 patients (up 500 from each type of surgery, although the numbers recruited from each surgical specialty may vary).

We will recruit from two hospitals, Bristol and Southampton; we have experience in recruiting patients undergoing surgery from both these centres. The overall duration of the study will be 4 years.

The team includes a patient, surgeons, doctors with expertise in treating pain in the different types of surgery, researchers with expertise in conducting clinical trials and a health economist.

Further information

https://bristoltrialscentre.blogs.bristol.ac.uk/details-of-studies/gap/